Displacement transducer

Provided is a displacement amplifying device which uses Pascal's principle and is insusceptible to temperature change. A main body (1) is provided with an accommodation space (11) for accommodating a medium (2) therein. The medium (2) is provided with a fluid (21) with a positive thermal expansion coefficient and a movable body (22) with a negative thermal expansion coefficient. The movable body (22) is displaced according to the movement of the fluid (21). The medium (2) is provided with a small-area first movable surface (23) and a large-area second movable surface (24). The displacement of one of the first movable surface (23) and the second movable surface (24) is transmitted to the other via the medium (2). In the displacement amplifying device, even if the volume of the fluid (21) is changed by the temperature change of the medium (2), the amount of change of the volume of the medium (2) as a whole can be kept low by the volume change of the movable body (22).